Originally proposed as a technological solution that would forestall official
censorship, content filtering has been shown to pose its own signicant
threats to free expression on the Internet. Often characterized by their
proponents as mere features or tools, filtering and rating systems can
also be viewed as fundamental architectural changes that may, in fact,
facilitate the suppression of speech far more effectively than national
laws alone ever could.

This newly revised edition addresses recent developments, including new
content control legislation in the United States, efforts within the European
Union to establish a uniform rating regime for online material, and the
growing controversy over the use of filtering in public libraries. Partly
as a result of the writings contained in this collection, the headlong
rush toward the development and acceptance of filtering and rating systems
has slowed. These critical views must be considered carefully if we are
to preserve freedom of expression in the online world.